This project would look like some PCI slot risers, but incorporate a voltage shifter circuit to allow 3.3V only PCI cards to operate safely in a 5V only motherboard slot.
This is my long-term project to create a new Amiga motherboard for OS4. It's never got further than specification of major components and connections. After Nvidia removed the Uli M1575 southbridge, and Apple removed the PA Semi PA6T-1682M CPU from consideration, this project has lived in "what do I do now" limbo but has not been completely abandoned. I absolutely believe that a modular method is the way to go for small-market Amiga system design, which is central to this project. (Note that A-Eon has somehow resurrected the PA6T chip for their AmigaOne X1000 desktop computer)
I'd like to make a small, low-profile slot adapter board to allow a PCI-Express desktop low-profile plugin card to fit into a conventional PCI32 slot on a motherboard. Starcom has now made nearly exactly what I had in mind, this project may be void. If they change it to have a physical PCI-Express x16 slot, even if only x1 is connected, then that's exactly perfect, and they did seem interested in a future revision to do that. Until then, either cut the back end of the x1 slot, or get a x16 slot to swap on the board like I plan to do. I ordered two of these from Amazon, but received something different than what was pictured. :( :( I received two adapters of the opposite direction, plugs into a PCI-Express socket and takes a conventional PCI card on top, so I need to return and hope they have some correct items on the warehouse shelf. I'll be bummed to get more of the same wrong thing... Ah, Sintech has made the bridge I want! Look for them on ebay.
I'd like to make a low-profile desktop PCI -Express plugin board with a popular PC Southbridge chip to see if I can get the thing to work over a standard PCI-Express slot, including when a PCI-Express switch chip is involved. I have begun actual work on schematics for this, but have a ways to go before layout can begin.
No software needed automatic monitor input switcher. This would mostly be useful for autoswitching between Amiga native graphics output and a Video card such as Radeon. Might be interesting to also convert Amiga's video signal to standard VGA (Scandoubler + Flickerfixer capability) as well as to digital DVI.
Small PCB to buffer Efika motherboard's IDE port. I understand there's not many using IDE/PATA CDROM with Efika due to weak drive on IDE port limiting trace/cable length, especially with two IDE devices. I'd like Efika in a case with CDROM as well as hard drive or compactflash.
Amiga CPU accelerator board with two major modes. First is to implement a 680x0 CPU inside an onboard FPGA, intending to outperform old standalone 68k CPUs. This FPGA core CPU would have a fast memory bus to SODIMM or uDIMM slot. Second major mode would be as an adaptor to a modular accelerator using an industry standard format, adapting likely via PCI bus or perhaps PCI-Express bus to the module. This secondary mode would allow use of PowerPC or perhaps other CPU platforms in this standard module format, and the FPGA would bridge to the Amiga motherboard bus.
George Braun's website (in German, Google translated) has a number of Amiga projects, many with Eagle files available. The Wayback Machine shows us some additional projects(also Google translated), but the old Eagle files once available were not archived, so we can't rip them from there for things no longer on his own page :( . His most famous is a replacement motherboard for the A1000, which has a dedicated support website.
Dan Struther's Eagle Library at Bitbucket has Xilinx, PCI, Commodore, and other stuff. Not sure if these are unique things or his own copies of other stuff. But his blog does have some interesting board and FPGA projects.
I plan to have an Eagle parts library of Amiga-related pieces on sourceforge hopefully including components from the EAB library (direct link, may need to login) for Amiga projects as well as other items from EAB. For the moment, while we all discuss licenses, the Megarray connector (AmigaOneXE/MicroA1 CPU Module connector) which I plan to contribute to the sourceforge repository is available as LGPL3 here. And the MegArray is now also in the Sourceforge repository as GPL3.
Interesting Projects
- Wikipedia has a list of Open-Source hardware projects, some of which are FPGA things.
- Dan Struther's blog talks about his PCB projects, including a Spartan6 FPGA board.
- Other peoples' interesting projects, many from EAB forum threads (Build your own Amiga Hardware), largely thanks to user Zetr0.
Someone posted a free Eagle PCB library with Amiga-related items in this forum thread (Are you an Eagle CAD user?).Eagle parts libraries:
Connector Information: